ARP 126 - Building an AR-15 from Scratch - Part 4


Welcome to Episode #126 of the AR15 Podcast. I’m your host Reed Snyder and with me tonight is my co-host, J.W. Ramp.  This is the podcast about your favorite black rifle!  This show is for you; whether you're building your first AR or you’ve been building ARs for years. There is something we can all do to take our black rifle to the next level. Brownells helps make this show possible.

Don’t forget that Brownells, with their 100% lifetime satisfaction guarantee, is there for you anytime you have a problem, like when you can’t remove the taper pins from your new barrel to slip off the front sight base and you now have to find a new barrel.

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Shop for AR-15 parts at Brownells.  Go to:

Main Topic:  Building an AR-15 from Scratch - Part 4

The Building the Upper Receiver

  1. Upper Receiver
    1. Forward Assist
    2. Ejection Port Cover
    3. Lapping the Receiver
  1. Install Barrel
    1. Attaching to the receiver
    2. Torque
    3. Gas Tube Alignment Tool
    4. Anti Seize/Galling compound
  1. Install Gas Block/Sight Base
    1. Taper Pins
    2. Dimpled
    3. Clamped
    4. Gas Tubes
  1. Prepare BCG
    1. Extractor Upgrade Kit
    2. Lubrication
    3. Visual Check of Components
  1. Prepare Charging Handle
    1. Lubrication
  1. Install Handguard
  1. Install Muzzle Device
    1. Crush Washer
    2. Peel Washer
    3. Shims
    4. Visually inspect diameter

Otis Technology:

April 20: Eric Strong

April 27: Michael Blace

May 4:  Koal McMillan

May 11: Len Dichtel

May 18: @spillicious

The fine folks at Otis Technology have sent over a mountain of rifle maintenance tools and cleaning kits for the AR-15 and AR-10.  We’ve been tasked with giving them away.  Watch for the special posts on Facebook and Instagram to get a chance to win some of the awesome products made by Otis Technology.  We’ll give away a complete MSR Cleaning kit in either 5.56 or 7.62 in the middle of each  month up until Christmas, when we’ll give away a complete Otis Technology Elite Cleaning System to one lucky listener.  During the alternating weeks, we’ll be giving away a host of Otis tools and cleaning supplies.


Myles:  Hello, it has really been too long since I sent in a message. Oh, before I get going I wanted to thank you for your recent interviews with the factory reps from FN and Faxon. I have been curious about the Faxon arak for years as it looks like it resolves most of my issues with the AR design. I hope to get an arak 31 not long after they become available. Especially if they decide to make their rail in Mlok (hint hint).

On to the meat of the matter. This fellow Jeremy wants an AR in 7.65x54 rimmed, Russian? Well I am afraid he is out of luck. The closest such animals that I know of are the Noreen bad news rifles in 2006.

Here is a crappy pic of me and muh beard holding one in 338 Lapua at the local Cabelas.  And this little number which I think is only available in Europe.

If one wants an autoloader in this caliber I think your only options are to get a used Romanian PSL or a Molot vepr. Both are pretty uncommon.  Oh and for future episode subject matter may I suggest having a look at the sig mcx. Or perhaps a look at the new rifles by American defense.

Chad:  Reed,  for putting in the front pivot pin, I use a 1/4" clevis pin that you can get from the hardware store for a couple bucks. It works just like the tool from brownells.

Rusty F:  Guys thanks for your podcast and thank you to Brownells for sponsoring it. I listen via the Stitcher radio app on my Android

One tip I thought I'd pass along for anybody doing home gunsmith work. Go to a local store that sells second hand sporting goods and pick up a couple of hockey pucks. They are great for using on your workbench to put under things to either protect parts or change the angle on something you're working on.

Thanks again.

Mark M:  Just listened to full episode and I would concur on the 6.5 Grendel show. I am almost done with my build, 80% lower is in process. AR Performance barrel 18" melonite in 6.5G/264LBC, Ares Armor bolt carrier, Timney trigger.  There is a big debate about using the official 6.5 Grendel chamber vs Grendel II or 264LBC chamber.

Joe:  I recently started listening with episode 89 & I noticed you missed some ideas for truck bed storage. Here are links to some other ideas that are more stealthy than the ones you mentioned, especially if they are seen all the time in your vehicle.

Joe:  While designed to go on your arm you might be able to figure a way to attach it to your AR.

Steve:  Hey guys as always I really enjoy the show, especially the build portion you are doing currently, I have a two part question-first I am working on building a 308 style target rifle, I have been researching carbon fiber handguards and found one by Precision Reflex at Brownells , do you guys have any experience with this company in reference to it holding up with a 308 caliber. Secondly, the base rifle I am adding it too is an Armalite AR 10, this is probably going to sound like a dumb question but how exactly do I free float the rail, or by mounting the new one it becomes free floated?? I don't really understand the free float process. lol I wanted to get your input before starting this little project.

Larry C:  You mentioned how hard it is to install the pivot pin. I found the site below and using a clevis pin made it so much easier and it was cheaper than other tools I found. Evertt B:  Hello again Reed, Anthony, JW, and everyone else at the AR15 podcast and FRN. Thanks to tax returns, palmetto state armory, and your podcast, I just finished my first AR. I haven't gotten to shoot it yet, but plan to either today or tomorrow (if the weather holds). I ordered the Freedom rifle kit from palmetto, which seems great quality especially for a first rifle and a good platform to buy upgrades. The build was a blast and doing it together with my 17 year old son made it so much better. We planned to do a pair of rifles as a father/son project but had to settle for a "shared" rifle for now. As we upgrade parts on this one I plan to save what we take off to do a second rifle. I almost had a "lime-green linoleum" moment. While trying to install the pivot pin and detent my hand slipped and next thingI knew I heard something hit the ceiling and bounce off the back of my shoulder. Thank God my son has better eyesight than me. He found the detent and we got it installed. The hardest part of the build was believe it or not the trigger guard pin. It simply didn't want to move. We eventually got it in but I figure that trigger guard is never going anywhere. I did have a couple of questions. First off the palmetto rifle kit came with a pre-assembled upper with their 16" stainless barrel with a mid-length gas system. Is there anything specific to the stainless barrel I should watch for? Or with the mid-length gas system. Doesn't most 16" barrels use a carbine length system?  Why mid length? Well before this gets any longer thanks for the great show and all the info you give every week.

FB: Jesse L: Hello Reed. Listening to the last show building from scratch part two, I realized I might have a tip to share with you.  See The hole in the spring channel for the front pivot pin?

If you drop your spring in the depress the spring with a punch, you can capture the spring with a small flat screwdriver. Now while hold the spring compressed with the screwdriver, remove the punch, drop in the detent, then slide the pivot pin in, remove the screwdriver and you’re done!! By far the best way I have found to do this part of the lower!!

Tom G: Thanks for the refresher on building AR's and sorry I forgot to tell you the lower is the Spike's/Sharp Bros designed Warthog on my 6.8spc build.  It's at the shop getting Cerakote paint job in Texas Tan will post a pic when I get it back.  I will shoot iron sights until the scope becomes available.

I have a Tegra carbon fiber lower that I am thinking of doing a build with.  Making it as light as possible and seeing how it does with the recoil.  Sometimes when you get too light you get another set of problems but I would like to try it out.

Instagram: @jonjon_mclain:  Great show series going on right now!  I like the advice to consider all the options for the application.  In my experience, high cost is not always directly related to performance.

@mray22925: Range time with subsonic .22

@lifebehindagun:  The MK12 mod 0  build is all done. Next on to the 300blk.  #PRI #leupold #mk12 #igmilitia

@aledbetter: Sneak peek at the new build lightweight AR15 almost done.  Goal is under 4.5 lbs, under budget and nice to look at.  #tegarms #battlelinkminimaliststock